Endovascular grafting for abdominal aortic aneurysms

Despite the initial success of endovascular grafts in a very difficult patient population, many problems remain. These procedures are often time-consuming and quite complicated, requiring the close cooperation of an experienced team of vascular surgeons and interventional radiologists. Access may be difficult through occluded, stenotic, and tortuous vessels. Inadequate graft deployment may result in arterial rupture or graft migration, which could potentially lead to acute occlusion of the renal or iliac arteries. Occlusion of the inferior mesenteric artery may result in ischemic colitis. Also, endovascular grafts may fail to exclude an aneurysm from systemic arterial blood pressure, not protecting the patient against impending rupture, and embolization and thrombosis are ever-present dangers. Concerns have been raised regarding radiation exposure and intravenous contrast loads used during these procedures. Clearly, more experience must be gained and technologic advancements made before the use of these devices becomes commonplace, something that may not be too far off in the future.     

Endovascular treatment of abdominal aortic aneurysms: case report and review of literature

A case of endovascular treatment of abdominal aortic aneurysm is discussed along with a review of the literature. This recently introduced Food and Drug Administration Phase II treatment modality may have a significant impact on the approach to the treatment of aneurysmal disease. This discussion details the treatment of one typical patient and reviews the current status of endovascular therapy as it applies to infrarenal abdominal aortic aneurysms.     

Non-surgical treatment of abdominal aortic aneurysms

Percutaneous placement of an endovascular stent, with and without coils, in the treatment of large AAA in animal models is feasible, safe and effective. The covered stent sealed off AAA immediately after stent placement, however, it interrupted blood flow into arteries in the area covered by the stent. The uncovered stent prevented further expansion of the aneurysm and also significantly decreased the incidence of rupture. The long-term patency of branch arteries by the uncovered stent supported the possibility of safely using this approach in humans. Furthermore, either covered stent or uncovered stent with additional coils have the potential for treatment of acute aneurysm rupture or leaking. Most importantly, the aneurysm lumen in our model was gradually replaced by collagen after stent placement which further reduces the risk of aneurysm rupture: and this healing process was enhanced by the addition of coils. If proven safe and effective for humans as well, this technique has the potential for substantially reducing the morbidity and mortality associated with AAA.     

Diagnosis and treatment of abdominal aortic aneurysms

Abdominal aortic aneurysms occur in 5 to 7 percent of people over age 60 in the United States. An aneurysm is defined as a permanent localized dilatation of an artery, with an increase in diameter of greater than 1.5 times its normal diameter. Abdominal aortic aneurysms may be manifested by catastrophic rupture, signs of pressure on other viscera or an embolism originating in the aneurysmal wall, but most cases are asymptomatic. The diagnosis is often made by physical examination of the abdomen, which reveals a pulsatile mass left of the midline, between the xyphoid process and the umbilicus. The diagnosis may be confirmed by B-mode ultrasound. Ultrasound screening should be considered for individuals at risk for abdominal aortic aneurysms. This group includes individuals over age 60 who smoke, have hypertension or have vascular disease. Elective surgical intervention is indicated for most patients with abdominal aortic aneurysms greater than 5 cm in diameter to prevent rupture and death. Smaller abdominal aortic aneurysms should be monitored by regular ultrasound measurements. Screening and identification of abdominal aortic aneurysms by primary care physicians can have a significant impact on patient survival.     

Results of surgical treatment of ruptured abdominal aortic aneurysms

This paper analyzes results of 5-year surgical treatment of patients with ruptured abdominal aorta aneurysms (1991.-1995.) at the Clinic for Vascular and Transplantation Surgery of the Institute of Surgery in Novi Sad. 105 patients with abdominal aorta aneurysm underwent surgery, whereas in 31 patients there was a suspicion of rupture and it was confirmed by US and CT examination. One of basic factors to decrease mortality in these patients is early diagnosis and surgery before hemorrhagic shock occurs. Results in hemodynamic stabile patients with blood pressure over 100 mmHg and regular diuresis are much better with mortality of 20%. In order to estimate the correlation of hemodynamic state and outcome of the operation, patients were divided into three groups--hemodynamic stable with blood pressure over 100 mmHg and regular diuresis at admission: hemodynamic unstable patients with signs of mild or moderate shock and blood pressure under 100 mmHg and without initial diuresis which was regulated at the beginning of therapy and hemodynamic unstable patients in severe shock and unmeasurable blood pressure. The highest survival rate (10% mortality) and the least complications occurred in the first group of patients. The total mortality of patients after surgery was 48.48%. Timely diagnosis, suspicion of rupture and adequate first and with urgent transfer to a competent surgical institution are key factors in treatment of this disease and its outcome.     

Clinical aspects and treatment of inflammatory abdominal aortic aneurysms

An increasing number of inflammatory abdominal aortic aneurysms are reported today, although it is not clear whether these are nosologically independent lesions or a particular evolution of atherosclerotic aneurysms with enhanced phlogistic processes and fibrous reaction. Several pathogenetic theories have been proposed (microfissuration, autoimmunity, lymphatic stasis); clinical symptoms are characterised by the frequent involvement of contiguous retroperineal structures (in particular the urinary excretory tract and duodenum) which may be dislocated or compressed by the neoformation. CT or NMR appear to be the instrumental tests which give the most reliable diagnosis regarding the suspected inflammatory nature of the aneurysm. A correct pre-operative diagnosis is particularly important given that the morphological peculiarities (fibrosis and tenacious synechiae) add considerable pitfalls and difficulties to the operation. In this respect, the use of special technical devices, such as minimum dissection, permit a marked reduction of perioperative complications.     

Ruptured abdominal aortic aneurysms: factors affecting the early postoperative outcome

Long-term experience with 63 polyurethane, pail handle, coiled tip peritoneal dialysis catheters surgically implanted in 57 consecutive patients with renal failure is presented. One hundred percent follow-up of the study group represented 1,248 patient-months of observation. Cumulative catheter survival rates were 80.8% at 12 months, 62.3% at 24 months, and 48.1% through 51 months. Catheter half-life was 32.6 months. Infection was the most frequent catheter related complication. Incidence rate of peritonitis was 0.73, and exit site/tunnel infection was 0.42 episodes per patient-year. Median time to first episode was 11.7 months for peritonitis, and 26.3 months for exit site/tunnel infection. Infection led to removal of 28.6% of implanted devices, mechanical blockage resulted in 6.4% loss, and pericatheter leak and tubing break each accounted for 1.6% of catheter removals. The polyurethane, pail handle, coiled tip peritoneal catheter was found to be a reliable long-term access device compared with reported performances of other catheter types. An adverse outcome was identified in the current clinical series with a model design using a permanently attached catheter adapter that caused large exit site wounds that were predisposed to infection and catheter loss.     

Endovascular stent graft repair of aortic aneurysms

Vascular surgeons are increasingly encountering older patients with large aneurysms associated with severe comorbid conditions. This situation can increase operative morbidity and elevate the mortality rate of aortic surgery over 60%. With some frequency many patients will represent a prohibitive risk for conventional graft replacement. The endoluminal treatment of 110 patients has proved to be feasible and may represent an alternative solution. One hundred six of the patients had an abdominal aortic aneurysm and in four patients, the thoracic aorta was involved. All of them underwent endoluminal repair for the aortic pathology using the combination of stents and grafts in aorto-aortic or aorto-iliac position, with straight, tapered, or bifurcated stent-graft devices. The results are as follows: Initial success was 84% in aorto-aortic abdominal devices and 100% in aorto-aortic thoracic devices. In aorto-iliac devices, initial success was 75%. Late success rates were 62% of the initial group and 80% of the initially successful group.     

Chronic rupture of abdominal aortic aneurysms

INTRODUCTION: Rupture of abdominal aortic aneurysms (RAAA) can take place in one of the 4 following ways: 1. "Open" rupture in the free peritoneal cavity; 2. "Closed" rupture with formation of retroperitoneal haematoma; 3. Rupture into surrounding cavity structures, such as veins and bowels; 4. In rare cases rupture is effectively "sealed of" by the surrounding tissue reaction, and retroperitoneal haematoma is "chronically" contained [1]. The terms "sealed" [2], "spontaneously healed" [3], "leakig" [4] RAAA, were also used in the previous papers connected to this situation. The "sealed" rupture was first described by Szilagyi and associates in 1961 [2]. In their case the rupture was small and haemorrhage was effectively encircled by the tissue surrounding the aortic wall. The slow rate of blood loss contributed to the patient's haemodinamically stable condition. Christenson et al. reported a case of "spontaneously healed" RAAA [3]. Rosenthal and associates described 2 patients who had aortic aneuryms that ruptured several months before repair and contributed to the term "leaking AAA" [4], while Jones et al. introduced the term "chronic contained rupture" [1]. The aim of this paper is the presentation of 5 such patients. CASE REPORT: Between December 1, 1988 and May 30, 1997 411 patients with abdominal aortic aneurysms (AAA) have been operated at our institute. Of this number 137 (33%) had RAAA, while 5 patients (12%) had a contained RAAA (CRAAA). CRAAA were found in 3 male and two female patients, average age 62 years. All of them had a previously proved AAA and initial symptoms lasted for days or months before the admission. In all patients haematocrit, pulse rate and arterial tension during the admission, were normal. All typical signs of RAAA were absent in these patients. Patient 1. A 56-year-old man, smoker, with previous history of arterial hypertension had an isolated episode of abdominal pain and collapse 30 days before the admission. Physical examination revealed a pulsatile abdominal mass. Doppler ultrasonography identified an infrarenal AAA, with right lobular extraaneurysmal mass which displaced the inferior vena cava (ICV). Angiographically (Figure 1a) an unusual saccular intrarenal AAA was detected, while simultaneous cavography (Figure 1b) confirmed the-dislocated inferior vena cava to the right. The intraoperative finding showed infrarenal CRAAA with organized retroperitoneal haematoma between AAA, ICV and duodenum. After aortic cross clamping and aneurysmal opening, the rupture at the right posterior aneurysmal wall was discovered. The partial aneurysmactomy and aortobilliar bypass procedure with bifurcated knitted Dacron graft (16 x 8 mm), were performed. The patient recovered very well. After a 4-year follow-up period the graft is still patent. Patient 2. A 72-year-old woman with low back pain, fever and disuric problems was urgently admitted to the Institute of Urology and Nephrology. The standard urological examination (X-ray, intravenous pyelography, retrograde urography, kidney Duplex ultrasonography) excluded urological diseases. However, intrarenal AAA an a giant aneurysm of the right common iliac artery, were found. The proximal dilatation of the right excretory urinary system was also found by retrograde urography. The patient was transported to our Institute 20 days after the initial symptoms. Translumbar aortography (Figure 3) showed the right common iliac artery aneurysm and gave the false negative picture of normal abdominal aorta because of parietal thrombosis of AAA. The intraoperative finding showed chronic rupture of the posterior wall of the right common artery aneurysm. The retroperitoneal haematoma compressed the right ureter. Both aneurysm have been resected and replaced by bifurcated Dacron graft (16 x 8 mm). The patient recovered successfully. After a 2-year period of follow-up the graft is still patent. Patient 3. (ABSTRACT TRUNCATED)     

Electron-beam CT-angiography in abdominal aortic aneurysms. Initial results

PURPOSE: To evaluate the suitability of ultrafast electron-beam tomography (EBT) for the investigation of abdominal aortic aneurysms using CTA. METHODS: Thirty-one patients with suspected abdominal aortic aneurysm were investigated with EBT using an Evolution XP scanner (Siemens, Erlangen) with the newest software version 12.34 with continuous volume scanning of 140 images in 17 s. Collimation was 3 mm, table increment 4 mm with overlapping image reconstruction every 2 mm, exposure time 200 ms (124 mAs), resulting in a scan-range of 28 cm. A quantity of 80 ml contrast material was administered (flow 4 ml/s). Visualization of the abdominal aorta and its branches was performed with MIPs and shaded surface display. Evaluation of image quality was based on a four-step classification scale (1 = good, 4 = insufficient) for the demonstration of the abdominal aorta and the visceral, renal and iliac arteries. RESULTS: All EBT examinations demonstrated high and homogeneous density values along the whole vessel course with a mean density value of 258.7 +/- 47.3 HU for the abdominal aorta and the iliac arteries. Quality evaluation for the vessel demonstration showed mean values between 1.22 and 1.57 for the abdominal aorta and the visceral, renal and iliac arteries. CONCLUSIONS: EBT with 140 slices and slice reconstruction every 2 mm offers a high z-axis resolution resulting in high-quality CT angiographies of the whole abdominal aorta and its branches.     

Preservation of masculine sexual functions after treatment for abdominal aortic aneurysms

Preserving sexual function is an important objective in the treatment of aneurysms of the abdominal aorta in men. METHOD: Two groups of patients with normal sexual function were operated for aneurysms of the abdominal aorta. In group 1 (n = 22) a small opening in the infra-renal aorta was made for insertion of an aorto-bi-iliac prosthesis; in 4 of them, the aneurysm was not opened but simply excluded. In group 2 (n = 22), the aorta was opened longitudinally for insertion of an aorto-aortic tube. RESULTS: Sexual function was totally abolished after operation in 9% of the patients in group 1 and in 36% of those in group 2. Sexual functions were totally preserved in 50% of the patients in group 1 and in 36% of those in group 2, but the differences were not statistically significant. CONCLUSIONS: 1) It is not always possible to guarantee maintained sexual function after operation for aneurysms of the abdominal aorta and the patients should be advised thereto; 2) aortobi-iliac prostheses with limited opening of the aorta in the upper part of the aneurysm or exclusion of the aneurysm led to a higher rate of preservation than aorto-aortic tubes with total opening of the aneurysm and should be preferred in men with normal sexual function.     

Endovascular management of traumatic infrarenal abdominal aortic dissection

Dissection is a recognized finding after blunt trauma to the abdominal aorta. Immediate and long-term prognosis is poor without surgical treatment especially since most patients present severe associated injuries. On the basis of encouraging results using endovascular techniques to treat experimental dissection of the descending thoracic aorta, we treated three patients with traumatic infrarenal abdominal aortic dissection by percutaneous stent placement. There were two men 34 and 41 years of age and one 89-year-old woman. In all patients, dissection began in the infrarenal portion of the aorta and extended into the iliac arteries. All patients had multiple associated injuries. The main symptoms were acute abdominal pain (two patients) and ischemia of the lower extremities (two patients). Diagnosis was missed in one patient despite exploratory laparotomy for an associated injury. Two patients were treated in the acute phase by placement of a self-expanding endovascular prosthesis at the aortoiliac level. The third patient was treated in the chronic phase by placement of a balloon-expandable endovascular stent. All procedures were performed uneventfully by femoral route. Success of treatment was confirmed by arteriography and computed tomography (CT) scan demonstrating obliteration of the dissection. Upon late follow-up examination, all patients were in satisfactory condition, with normal Doppler ultrasound findings. These findings confirm experimental studies using endovascular treatment for dissection of the descending thoracic aorta and are promising for future clinical management.     

Endovascular treatment of internal iliac artery aneurysms

BACKGROUND: Homeless people with mental illness have relatively high rates of human immunodeficiency virus, comorbid antisocial personality disorder, and may be homeless more frequently and for greater lengths of time. All of these factors may increase the risk of tuberculosis. METHODS: Our study was done to ascertain if homeless men with psychotic disorders are at an increased risk for tuberculosis infection. One hundred fifty homeless men were interviewed and given purified protein derivatives (PPDs) at a downtown shelter in New Orleans, Louisiana, during a 3-month period. RESULTS: The findings show a strong relationship between psychotic disorders and positive PPDs, with a relative risk of 4.48. CONCLUSIONS: Homelessness and mental illness present barriers to seeking and completing treatment for medical illnesses such as tuberculosis. Use of services may be low even when available; therefore, homeless men with psychotic disorders may be serving as a reservoir for tuberculosis.     

Anatomical suitability of abdominal aortic aneurysms for endovascular repair

BACKGROUND: Aortic aneurysm anatomy is crucial when considering patients for endovascular repair. The aim of this study was to determine the proportion of patients with aortic aneurysm suitable for endovascular repair with three different graft-stent systems. METHODS: Spiral computed tomographic angiography was used to assess the anatomy of 154 abdominal aortic aneurysms. Measurements were made of aneurysm neck length and diameter, renal artery to aortic bifurcation length, common iliac artery diameter and length, and external iliac artery diameter. Aneurysms were assessed for anatomical suitability for currently available aortoaortic, aortobi-iliac and aortouni-iliac devices. RESULTS: Six patients (4 per cent) had a distal aortic neck suitable for implantation of a straight aortic graft. Fifteen patients (10 per cent) had arterial anatomy suitable for implantation of a bifurcated graft and 85 (55 per cent) patients were suitable for endovascular repair with an aortouni-iliac graft. The primary reasons for unsuitability were: proximal neck length less than 1.5 cm (44 patients), proximal neck diameter greater than 3.0 cm (12), and angulation of the proximal neck (three). A further ten patients were considered unsuitable for an aortouni-iliac graft because of bilateral common iliac artery aneurysms (four), tortuous iliac arteries (four) and narrow external iliac arteries (two). CONCLUSION: The aortouni-iliac device has the widest applicability of the currently available endovascular systems but open repair remains the only option for a large proportion of patients.     

A statistical analysis of the growth of small abdominal aortic aneurysms

Screening for abdominal aortic aneurysm has been offered to 13,000 patients. An overall compliance of 76% (range 51-99%) has been achieved. For those with an initial aortic diameter between 29 mm and 45 mm serial ultrasound scans are offered to monitor aortic change. Of the 302 cases followed up by repeated scans, 93 have had more than 5 scans (mean of 7 scans) over a mean time period of 32.1 months (range 15-63 months). The rate of change of all these aneurysms has been calculated using all data points and robust linear regression. It has been possible to postulate an algorithm for aortic growth. The influence of measurement precision and ultrasound quality assurance on the rescan interval is demonstrated and it is suggested that 2 years is a suitable rescan interval for aortas with diameter less than 40 mm.     

Endovascular abdominal aortic aneurysm repair. First experiences regarding 20 patients in Eindhoven

OBJECTIVE: Evaluation of the early results of endovascular abdominal aortic aneurysm (AAA) repair. DESIGN: Prospective cohort study. SETTING: Catharina Hospital, Eindhoven, the Netherlands. METHODS: Operative results and complications following endovascular AAA repair in 20 consecutive patients were surveyed. The early results consisted of the procedural outcome and the events during a mean follow-up of 6.6 months (range: 1-12 months). Nine patients had a considerably increased operation risk (American Society of Anesthesiology (ASA) class III of IV). Criteria for success were absence of endoleak and of further expansion of the aneurysm. RESULTS: Three of the nine patients in bad general shape suffered an episode of cardiac failure after the operation. In the other patients there were no serious systemic complications. No patient died. Sixteen patients (80%) had a successful immediate AAA exclusion. In two patients a second endovascular procedure was required to seal an endoleak. In one patient the procedure was converted to an open reconstruction because of a persistent endoleak, while in another patient a small midgraft endoleak was treated conservatively. Ultimately 18 patients (90%) had a successful endovascular AAA repair. CONCLUSION: Endovascular AAA repair is feasible with a high success rate and a low complication rate. This method is expected to gain an important place in future AAA repair. Longer follow-up is needed to study late complications, among which occurrence of early and late endoleaks is the most important.     

Experience of reoperations followed by repairs of abdominal aortic aneurysms

We experienced 8 cases who required reoperations, including 2 re-redo operations, after repairs of infrarenal abdominal aortic aneurysms. Of 8 patients, one patient developed a new aneurysm due to atherosclerosis in thoraco-abdominal aorta involving all visceral arteries and other 7 patients had aneurysmal formations at proximal anastomotic sites, including 3 suprarenal, 2 juxtarenal and 2 infrarenal aortic lesions. Etiology at initial operation in patients who subsequently developed anastomotic aneurysms included vasculo-Beh?et disease in 4, atherosclerosis in 2 and dissecting aortic aneurysms type III due to Marfan syndrome in 1. At reoperation, all who had vasculo-Beh?et disease had ruptures of anastomotic sites and 2 patients underwent repairs of dehiscent patch, 1 extra-anatomic bypass between ascending and abdominal aorta and 1 interposition of graft. One patient who had graft infection after repair of abdominal aortic aneurysm required axillo-femoral bypass with removal of infected graft. A patient who had dehiscence of proximal anastomosis after repair of aortoiliac occlusive disease required interposition of graft. Two patients, Marfan syndrome and aneurysm in thoraco-abdominal aorta, underwent graft replacement of thoraco-abdominal aorta concomitant with reconstruction of all visceral arteries. There were 8 patients who required reoperations for aneurysms at distal anastomotic sites after repairs of abdominal aortic aneurysms. Five patients underwent repairs of new aneurysms, including replacement of total arch in 3, descending aorta in 1 and iliac artery in 1. In all cases, no hospital death was noted, however, late deaths were occurred in vasculo-Beh?et disease, Marfan syndrome and graft infection. Thus, late result depends on etiology of disease. Although patients who requires reoperation after repair of abdominal aortic aneurysms have higher operative risk factors, early and late results are satisfactory compared to initial operations.     

Endovascular treatment of thoracic aortic aneurysm]

OBJECTIVES: The purpose of this study was to explore changes in breast-feeding initiation from 1979 to 1996 among infants born in New York City hospitals. METHODS: All New York City hospitals were surveyed every 2 years. Hospital staff reported feeding method at newborn discharge. RESULTS: New York City breast-feeding initiation rates increased consistently from 1979 to 1996 (from 29% to 58%, P < .0001), including 1984 to 1990, when rates decreased nationally. CONCLUSIONS: A 1984 New York State regulation requiring each hospital to designate a lactation coordinator may have been associated with the continuing increases in breast-feeding initiation.